Probes are mechanical tools for measuring electrical characteristics of microscopic electronic devices (e.g., semiconductor devices). As well known, a semiconductor device has pluralities of pads for communicate signals with an external electronic system. The semiconductor device may process electrical signals that are inputted through the pads, and then, the processed result is transferred to the external electronic system through the pads. The probes are arranged on a printed circuit board of a probe card, physically contacting with the pads, so that they form electrical paths for signal transmission with the external electronic system.
Probe cards, as well known, can be classified into needle, vertical, and cantilever types in accordance with kinds of probes. The probe cards are disclosed in Korean Patent Application No. 2001-0064603 or 2004-7021434. The needle-type probe card has a disadvantage such that probe needles may be distorted in horizontality and alignment due to repetitive use because the probe needles have insufficient restoring force. Additionally, since the probe needles of the needle-type probe card are large in size themselves, it is improper to be employed in testing a highly integrated semi-conductor device. The vertical probe card is otherwise appropriate for testing a highly integrated semiconductor device since it is smaller and probes are arranged in narrower intervals. But, the vertical probe card, as a force contacting a probe to a pad is directed toward a lengthwise direction of the probe, also has a problem of distortion due to an insufficient restoring force.
According to a typical cantilever-type probe card shown in FIG. 1, tips 2 contact with a pad 3 are bonded to an end of a cantilever 1, and the cantilever 1 is fixed to a printed circuit board (not shown) in parallel with a top surface of the pad 3. Accordingly, in this cantilever-type probe card, the force contacting probes (in detail, the tips 2) with the pad 3 acts in a direction perpendicular to a lengthwise direction of the cantilever 1. Such a structure of the cantilever-type probe card provides the sufficient restoring force thereto.